1. Field of the Invention
The present invention relates generally to an internal combustion engine and more particularly to an internal combustion engine having a single point injector which is operated to vary the number of injections per revolution of the crankshaft in accordance with various operating parameters of the engine.
2. Description of the Prior Art
In known single point injection (SPI) engines it has been proposed to energize the injector either once or three times per revolution of the crankshaft of the engine. However, these arrangements have suffered from the drawbacks that at low engine speed operation the single injection method has failed to provide an adequate fuel distribution to the cylinders, while the three injection method produces an acceptable fuel distribution at low engine speed but it is unable to maintain linearity between the injector trigger pulse width and the actual injection at high engine operation. This has been particularly the case in six (or more) cylinder engines wherein the rate of energization of the single injector is three times higher than in the case of multi point injection (MPI) wherein each of the six cylinders is fed fuel from an individual injector.